The captivating image of the dwarf irregular galaxy, UGC 8091, is a result of combining data from NASA’s Hubble Space Telescope’s Wide Field Camera 3 and Advanced Camera for Surveys. Depicting a billion stars, the galaxy resembles a dazzling snow globe in this festive snapshot, beautifully captured by the collaborative efforts of NASA and the European Space Agency (ESA).
Situated about 7 million light-years away in the Virgo constellation, the dwarf galaxy UGC 8091 earns its classification as an “irregular galaxy” due to its absence of a distinct spiral or elliptical structure. Unlike more ordered counterparts, the stars within this cosmic assembly resemble a radiant entanglement of string lights rather than a traditional galaxy. Irregular galaxies like UGC 8091 may acquire their peculiar shapes through tumultuous internal processes or interactions with neighboring galaxies, resulting in a diverse range of sizes and configurations, such as the diffuse scatter of stars exhibited by this captivating celestial entity.
This image was crafted by merging twelve camera filters, spanning from mid-ultraviolet to the red end of the visible spectrum. The radiant red patches signify excited interstellar hydrogen molecules illuminated by the intense light from hot, energetic stars. Meanwhile, the other luminous elements in the image comprise a blend of aging stars. Against the backdrop, a myriad of distant and diverse galaxies adds to the visual spectacle, all impeccably captured by the Hubble Space Telescope’s keen observation. The data behind this composition were gathered over the period from 2006 to 2021, using Hubble’s Wide Field Camera 3 and the Advanced Camera for Surveys.
The comprehensive observing programs contributing to this image aimed to explore the historical significance of dwarf galaxies in the process of reheating hydrogen that cooled during the universe’s expansion after the big bang, billions of years ago. Beyond this, astronomers are delving into the composition of dwarf galaxies and their stars, seeking to unveil the evolutionary connections between these ancient galactic entities and more contemporary galaxies, including our own.